- May 3 Tom Hartley, English cricket spin bowler (Test BB 7/62 v India 2024; Lancashire CCC), born in Ormskirk, England
- May 5 Nathan Chen, American figure skater (Olympic Gold 2022), born in Salt Lake City, Utah
- May 7 Cody Gakpo, Dutch footballer for Liverpool and the Netherlands, born in Eindhoven, Netherlands
- May 10 Nadia Ferreira, Paraguayan fashion model and beauty queen (Miss Paraguay, 2021), born in Villarrica, Paraguay
- May 11 Sabrina Carpenter, American actress (Girl Meets World) and singer, born in Lehigh Valley, Pennsylvania
- May 23 James Charles [Dickinson], American internet personality and model (Cover Girl), born in Bethlehem, New York
- May 25 Brec Bassinger, American actress (Stargirl), born in Saginaw, Texas
- May 27 Lily-Rose Depp, French-American actress (The Dancer) and model, born in Neuilly-sur-Seine, France
- May 28 Cameron Boyce, American actor (Mirrors, Jessie), born in North Hollywood, California (d. 2019)
- May 30 Guanyu Zhou, Chinese racing driver (first Chinese F1 driver), born in Shanghai, China
- May 30 Sean Giambrone, American actor (The Goldbergs - "Adam"), born in St. Joseph, Michigan
About May 1999
How Old? 25 years old
Generation: Generation Z
Leap Year: No
20-29
30-39
40-49
50-59
80-89
Over 90